default to binutils 2.18 on ppc* for manual selection as well

SVN-Revision: 14367

toolchain/binutils/Config.in

@@ -3,6 +3,7 @@
 choice
 	prompt "Binutils Version" if TOOLCHAINOPTS
 	default BINUTILS_VERSION_2_18 if TARGET_avr32
+	default BINUTILS_VERSION_2_18 if TARGET_ppc44x || TARGET_ppc40x
 	default BINUTILS_VERSION_2_17
 	help
 	  Select the version of binutils you wish to use.